Current status of zirconia-based all-ceramic restorations fabricated by the digital veneering technique: a comprehensive review.

OBJECTIVES: Delamination and chipping are major complications of veneering material on zirconia-based all-ceramic restorations. The digital veneering technique was introduced to overcome these complications as both zirconia frameworks and veneering ceramic are fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM). The aim of this review is to report all articles that evaluate zirconia-based all-ceramic restorations fabricated by the digital veneering technique. Three different digital veneering techniques were detected: the Lava DVS Digital Veneering System (3M ESPE), the Rapid Layer Technology (Vita Zahnfabrik), and the CAD-on technique (Ivoclar Vivadent). There are also some modifications of these techniques in the literature. MATERIALS AND METHODS: For this review, a comprehensive literature search was conducted. Detected studies are reported according to fracture resistance, flexural strength, wear performance, shear bond strength, microtensile bond strength, mechanical performance of restorations on implant abutments, marginal fit, color reproducibility, and clinical success for all types of digital veneering techniques. RESULTS AND CONCLUSIONS: Anatomical framework design and digital veneering using lithium disilicate and fusion porcelain might decrease the risk of chipping and delamination of veneering ceramic on zirconia-supported all-ceramic restorations. However, this result is mainly supported by in vitro studies. More clinical studies with a large sample size, longer follow-up period, and different fixed dental prosthesis designs are needed.

Clinical procedures, designs, and survival rates of all-ceramic resin-bonded fixed dental prostheses in the anterior region: A systematic review.

OBJECTIVES: The aim of this study is to systematically review all the clinical articles about all-ceramic resin-bonded fixed dental prosthesis (RBFDP) in the anterior region and assess their designs, clinical procedures, and survival rates. A systematic review was conducted after searching electronic databases PubMed/Medline and EBSCOhost Research Databases for articles published in English between 1987 and July 2017. MATERIALS AND METHODS: The inclusion criteria were selected as all clinical studies, original design clinical reports, and clinical reports (follow-up time more than 1 year) as all clinical information in the literature are desired to be included in the present review. RESULTS: The initial electronic search generated 472 articles from PubMed/Medline and 464 articles from EBSCOhost Research Databases. After selection of the articles as per the inclusion criteria, a final sample of 29 original studies is decided as: 1 randomized controlled clinical trial, 4 clinical controlled trials, 4 prospective cohort studies, 2 retrospective cohort studies, 6 original design clinical reports, and 12 clinical reports. After evaluation of the selected articles, it is likely that cantilever design all-ceramic RBFDPs are more successful than two retainer design in the anterior region; however, there is limited evidence for this result in the literature. CONCLUSION: Well-designed randomized controlled clinical trials with large sample size are still needed to achieve more accurate results about the clinical success rate of different RBFDPs designs in the anterior region. CLINICAL SIGNIFICANCE: Indications, designs, abutment teeth preparation, provisionalization, try-in, surface treatment options, and cementation of the all-ceramic resin-bonded fixed dental prostheses are described in this article. Clinical survival rates are also given in detail, so that clinicians can easily compare the current studies and give their own decision about all-ceramic resin-bonded fixed dental prostheses in the anterior region.

An earplug technique to reduce the gag reflex during dental procedures.

BACKGROUND: The gag reflex is a frequent problem occurring during dental treatment procedures, especially while making impressions of the maxillary teeth. The present study aims to evaluate the efficacy of a simple earplug as an external auditory canal stimulator to supress the profound gag reflex and as a second step, to map areas of the oropharynx suppressed by this technique. METHODS: In the first step of the study, 90 patients who had a gag reflex during the impression procedure were allocated to a study group, a sham group, and a control group for evaluating the efficacy of the earplug technique. Second, 20 new patients with a gag reflex were included in order to map the oropharnygeal areas suppressed by this technique. RESULTS: The severity of the gag reflex was reduced in the earplug group (but not in the sham or the control group). The affected area included the hard palate, uvula, and the tongue but not the posterior wall of oropharynx. CONCLUSION: An earplug technique can be a useful, practical, and effective tool to overcome the gag reflex during oral procedures, such as impression procedures of maxillary teeth.

Scintigraphic, histologic, and histomorphometric analyses of bovine bone mineral and autogenous bone mixture in sinus floor augmentation: a randomized controlled trial--results after 4 months of healing.

PURPOSE: To test our null hypothesis stating that the mixture of autogenous cortical bone scrapings and bovine bone mineral (BBM) in a ratio of 1:4, compared with BBM alone, would have no significant effect on new bone formation 4 months after maxillary sinus floor augmentation. PATIENTS AND METHODS: Twenty-four patients presenting with alveolar bone height of less than 5 mm in the narrowest zone between the sinus floor and alveolar crest were randomly assigned to 2 treatment groups in this randomized controlled trial. We augmented 12 maxillary sinuses with a mixture of BBM and cortical autogenous bone graft, which was collected from the lateral wall of the maxillary sinus by a bone scraper, and 12 maxillary sinuses with BBM alone. Four months postoperatively, new bone formation in the augmented sinus sites was evaluated through bone scintigraphy, as well as histologic and histomorphometric analyses of the biopsy specimens obtained during implant placement. Data were statistically analyzed by independent-samples t test. RESULTS: Scintigraphically detectable new bone formation did not differ significantly between the groups (P > .05). Histologic findings showed that the new bone bridged between BBM particles and BBM underwent resorption by osteoclasts with or without the addition of autogenous bone graft. According to histomorphometric findings, the difference between the percentages of newly formed bone in the sinuses augmented with graft mixture (25.73%) and BBM alone (24.19%) was statistically nonsignificant (P > .05). CONCLUSIONS: The addition of autogenous cortical bone scrapings to BBM in a ratio of 1:4, compared with BBM alone, does not markedly increase new bone formation 4 months after maxillary sinus lifting.

Decontamination of autogenous bone grafts collected during dental implant site preparation: a pilot study.

Dental implant site preparation produces bone particles that can be used as autogenous bone graft material for the reconstruction of alveolar bone defects; however, collected bone particles are contaminated with oral microorganisms that may cause augmentation failure due to complications associated with infection. The stringent aspiration protocol, preoperative oral chlorhexidine rinsing, and antibiotic prophylaxis were implemented before collecting bone particles. Nonetheless, collected bone particles were still contaminated with bacteria, and, therefore, decontamination of the collected bone particles with chlorhexidine or clindamycin was considered. The aims of this study were to quantitatively determine the degree of bacterial contamination of collected bone particles and to quantitatively evaluate the efficacy of treating collected bone particles with clindamycin or chlorhexidine solutions. Both of the agents effectively decontaminated the collected bone particles. Comparison between these antimicrobials in further studies could be useful in determining which is most effective.

Decontamination of autogenous bone grafts collected from dental implant sites via osteotomy: a review.

Autogenous bone particles can be obtained with bone collectors during implant osteotomy; however, collected bone particles contain oral microorganisms that may cause infectious complications. The purpose of this review was to summarize the clinical studies that have evaluated the degree of this contamination and the effectiveness of different decontamination methods. Stringent aspiration protocol, preoperative oral chlorhexidine rinse, and antibiotic prophylaxis are important precautions to be implemented when collected bone particles are to be implanted. Despite reducing contamination of collected bone particles, none of the methods described in the literature can completely decontaminate collected bone particles or prevent the risk of infectious complications. Further research is needed to identify more effective decontamination methods.

Required minimum primary stability and torque values for immediate loading of mini dental implants: an experimental study in nonviable bovine femoral bone.

Immediate loading of implants decreases the period a patient has to remain edentulous. However, for successful immediate loading in clinical practice, a strong initial fixation with bone is a prerequisite. In the present study, it is aimed to measure the primary stability, minimum placement, and removal torque values of mini dental implants which were originally designed for immediate loading. Therefore, mini dental implants (10, 13, 15, and 18 mm length and 1.8 and 2.4 mm diameter) were inserted into nonviable femoral bovine bone with a physiodispenser which can show the torque values digitally. After the implants were inserted, the primary stability values were measured with Periotest. Then the implants were removed from the bone using the same physiodispenser and the removal torque values of the implants were measured. Finally, 3 related tables were created, which show the match of the 3 different values (primary stability, placement, and removal torque) for each implant. The best Periotest values are -8 to +9, which reveal the best primary fixation range. In the tables, placement and removal torque values that correspond to this range are observed. In conclusion, it is believed that the results will aid the dentists in their decision for the selection of the Periotest value ranges and their related placement and removal torque values to decide for immediate loading of the mini dental implants. Mini dental implants, which are especially designed for immediate loading, can only be loaded immediately if their Periotest values (and their related placement and removal torque values) are measured to be between the range of -8 to +9. It is believed that the placement and removal torque values below the -8 to +9 Periotest range are not suitable for immediate loading procedure. Because this study concentrates only on experimental results, further clinical research is needed to be made in order to draw more definite conclusions about immediate loading of the mini dental implants.

A mini dental implant-supported obturator application in a patient with partial maxillectomy due to tumor: case report.

Following a partial maxillectomy in a patient, the oral and nasal cavities remain open, providing a passageway for transmission of air and fluids between the 2 cavities. In such cases the primary aim should be the construction of an implant-supported obturator prosthesis with adequate retention, stability, and peripheral seal. In this case report, a 34-year-old female patient who underwent a class II (according to Okay et al.) partial maxillectomy 14 years before was fitted with an obturator that was supported by 5 mini dental implants. The reason for the preference of mini dental implants is the lack of adequate bone tissue for conventional implant placement in the resected area and the placement of mini dental implants with a simple surgical procedure. The treatment achieved restoration of the lost functions, which satisfied the patient, restoring her self-confidence and enhancing her quality of life. Thus, applying obturators supported by mini dental implants was successful and may be considered as an alternative to more complicated surgical techniques. Although the presented case is promising, further clinical research is needed to draw more definite conclusions.

Treatment of a narrow, single tooth edentulous area with mini-dental implants: a clinical report.

The narrowing of an extraction site often becomes problematic when attempting to restore the space with a conventional wide-diameter implant. A woman is presented who was treated with a square head, mini-dental implant-supported fixed denture for a maxillary with a narrowed edentulous area, with a mesiodistal width of 5 mm. The implant, with a diameter of 2.4 mm, was inserted without reflecting the mucoperiosteal flap and was loaded immediately. During 12 months of follow-up, there has been no bone resorption and no inflammation observed around the implant. In conclusion, in terms of both clinical and aesthetic criteria, small diameter, mini-dental implants can be successfully used as an alternative to treatment with fixed partial dentures.